Operation Build-A-Reef

Great News For Oyster Lovers!

We planted 72 million oysters in 2022!

The Severn River Association and the Oyster Recovery Partnership are thrilled to announce that the Severn River Build a Reef planting is happening! A total of 72 million spat-on-shell (baby oysters) found new homes on reefs in the Severn in 2022. Thanks to the generosity of individuals, as well as local businesses and foundations, the community’s stewardship is helping to make positive changes to the Severn River estuary a reality!

With your help again this year, we’ll launch another Operation Build-A-Reef and plant another 25 million oyster spat-on-shell later this summer.  It’s all part of a grand strategy to bring oysters back to the Severn River. One day we hope to have billions of oysters cleaning and filtering the river.

It’s not too late to support Build a Reef! Every dollar contributed plants 100 oysters!

The Severn watershed drains a large, densely-populated area. As a result, our communities experience erosion, degraded water quality and other pressing issues. Anne Arundel County is working hard on land-based clean-up efforts.

Your sponsorship enables the plating of water-filtering oysters to help repair the river from within.

Operation Build-A-Reef expands upon significant progress made during the summer of 2018, when over 47 million oysters were planted on protected oyster sanctuaries between the Severn River and U.S. Naval Academy bridges. It is a collaborative partnership between the Severn River Association and the Oyster Recovery Partnership.

As friends and neighbors, businesses and community organizations, let’s do more than imagine a health Severn River… let’s make it happen!

A bit of history …

For thousands of years, oysters thrived in the Severn. They had a strong effect on the nature of the river itself, creating fisheries and influencing human life along these shores.

Fast forward to today – over harvesting, pollution, stormwater runoff, dead zones, diseases, algae blooms and increased sediment from development virtually eliminated our once thriving oyster reefs. Fortunately the Maryland Department of Natural Resources and others have stepped up to start restoring our historic oyster reefs, but we need to keep pushing ahead.

That’s why the Severn River Association and the Oyster Recovery Partnership created Operation Build-A-Reef.

The program solicits private donations to purchase millions of oyster spat (baby oysters) and plant them in the Severn River to repopulate and restore historic oyster reefs.

Why Oysters?

Because each oyster is small water-treatment plant. A mature oyster can filter up to 50 gallons of water per day! Oyster reefs also create the structure and habitat for other marine life to thrive and improve fishing on the river. 

Red areas are where Operation Build-A-Reef plants oysters

The red areas that naturalist, educator and former SRA board member John Page Williams is pointing to at right are the historic oyster reefs that Operation Build-A-Reef is repopulating with baby oysters.

In 2018 when the SRA/ORP partnership launched Operation Build-A-Reef, we leveraged support from the Maryland Department of Natural Resources with private donations to purchase 47 million oyster spat-on-shell from the Horn Point Hatchery in Cambridge, Md.

The Robert Lee at work on the Severn River.

To the left is the the Robert Lee in action planting oyster spat-on-shell on the first of four planting days in July 2018.

The Capital newspaper provided excellent coverage of the first day of planting. Click here to read the article, watch their video and check out some pictures of the July 23, 2018 event.

The Bay Journal, Chesapeake Bay Magazine, Hakai Magazine and SpinSheet Magazine each featured stories about Operation Build-A-Reef’s expansion of oyster plantings on Traces Hollow in 2021.

The oyster reefs selected for restoration were chosen because the have firm substrate on the river bottom that oysters can easily attach to and get to work cleaning the river.

Annapolis Mayor Gavin Buckley (left in dark blue) joins SRA President Lynne Rockenbauch (in light blue) at Build-A-Reef planting celebration. SRA Oyster Chair Bob Whitcomb in yellow cap.

SRA’s Water Quality Monitoring teams visit the reefs every week to track oxygen and salinity levels on the bottom where our bivalve pals live.

It will take billions of oysters to filter the entire river – from the mouth to the headwaters. As we launch Operation Build-A-Reef in 2020, we taking another giant step to recreating and repopulating our historic oyster reefs.

With your support, we can restore one of nature’s hardest working species and let them do what they do best – filter the water so that the Severn and its inhabitants can thrive now and into the future!


Severn River Association, Oyster Recovery Partnership,  Maryland Department of Natural Resources and the University of Maryland’s Horn Point Hatchery, Chaney Foundation, Flywheel, Beltway Companies, Capital Strategies, Maryland Renaissance Festival, Delaplaine Foundation, M&T Bank, Lures Bar & Grille, and Watermark.


Program Goal

Improve water quality to create a resilient reef habitat by planting and monitoring oysters that will perform their natural, historic function – to filter the water.

Program Outcome

  • Enhance conditions for fishing, swimming, crabbing, and other recreational activities.
  • Raise public awareness about the land-river connection.
  • Educate the public about ways to improve the river ecosystem
  • Improve and increase marine life (finfish and shellfish) habitat.

Photos: BlueMoon Photography